Mechanisms of surface wave plasma excitation and energy transfer from electromagnetic wave.

表面波等离子体激发和电磁波能量转移的机制。

基本信息

批准号：
10480100
负责人：
KANDO Masashi
金额：
$ 5.76万
依托单位：
Shizuoka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

项目摘要

Phenomena related to the surface wave plasma excitation have been found by Langmuir probe. They will be summarized as follow;1. Axial density profiles became moderate with the pressure decreasing.2. At the pressure lower than 50 mTorr, the dip appears on the probe characteristic curves detected around 1-2 cm from the quartz plate. Decreasing the probe bias voltage lower than -80 V with respect to the ground, the dip disappeared. This means that the dip is created by hot electrons which is produced by a certain electron acceleration mechanism.3. Measurement by the probe with a metal surface only on its one side showed that the electron flux with high energy flew down from quartz plate to the bottom of the discharge chamber.4. The signals picked up by dipole antenna which is set up at 5 mm from the quartz plate are frequency analyzed. As a result, three frequency spectra such as fィイD20ィエD2 = 2.45 GHz, fィイD21ィエD2 = 10 MHz and fィイD22ィエD2 = fィイD21ィエD2 + fィイD20ィエD2 are observed. Apparently fィイD20ィエD2 is the microwave frequency, while fィイD21ィエD2 corresponds to ion plasma frequency. Therefore, these phenomena is considered to be excited by so-called "parametric instability".In conclusion, Langmuir wave excited by parametric instability may transfer the energy to the electrons through a nonlinear phenomena such as Landau damping and then hot electrons produced here may contribute to the plasma production even though the electron collision with neutral particles were not so frequent because of a low filling pressure.

Langmuir探针发现了与表面波血浆兴奋有关的现象。它们将被总结如下; 1。随着压力降低，轴向密度曲线变得中等。2。在低于50 mtorr的压力下，倾角出现在距石英板1-2厘米左右的探针特征曲线上。相对于地面，降低探针偏置电压低于-80 V，倾角消失了。这意味着DIP是由热电子产品产生的，这是由某种电子加速机制产生的。3。仅用金属表面在其一侧的探针测量表明，具有高能的电子通量从石英板上飞向排放室的底部。4。分析了从石英板以5 mm设置的偶极天线拾取的信号。结果，观察到三个频谱，例如Fy D20E D2 = 2.45 GHz，FIC D21E D2 = 10 MHz和FIC D22E D2 = FIC D21E D2 + FIC D20E D2。显然，FIC D20E D2是微波频率，而FIC D21E D2对应于离子等离子体频率。因此，这些现象被所谓的“参数不稳定性”被认为是激发的。结论，通过参数不稳定性激发的Langmuir波可以通过非线性现象将能量传递到电子，例如Landau抑制，然后在这里产生的热电子也可能导致等离子的产生，即使电子碰撞与中性的压力并不经常填补，因此由于无法填补，因此也无法填补。